Power operated typewriter



' Oct. 22, 1.935.

w. J. PASINSKI POWER OPERATED TYPEWRITER Original Filed Jan. 25, 1930 3Sheets-Sheet 1 a m i? mJ mm l A N6 HM a& PM I Oct. 22, 1935. w. .1.PASINSKI 2,013,317-

POWER OPERATED TYPEWRITER Original Filed Jan. 25, 1930 3 Sheets-Sheet 2OR a/ierd Pawns/11' fiat Mil ATTORNEYS Oct. 22, 1935. w, PASINSK.2,018,317

POWER OPERATED TYPEWRI TER Original Filed Jan. 25, 1930 s Sheets-Sheet 3Fig. 4.

Y INVENTOR Mz/ferd Pas/n54;

7 53 lgbmaa ATTORNEYS Patented Oct. 22, 1935 UNITED STATES 2,018,317rowEa OPERATED .TYPEWRITER Walter J. Pasinski, Howell, Mich., assignorto Burroughs Adding Machine Company, Detroit, Mich a corporation ofMichigan Original application .lanuary 25, 1930, Serial No. 423,338.Divided and this application June 11, 1934, Serial No. 729,943. In GreatBritain January 25, 1930 Claims. (CL 197-17) This invention relates to apower operated typewriter. This application is adivision of my copending application, Serial No. 423,338, filed January 25, 1930.

The general object of the invention is to pro-- vide an improvedtypewriter of this type.

Another object is to provide a typewriter having improved means forshifting the platen by the power. v

A further object is to provide a machine of the foregoing class thatwill print characters of uniform distinctness independently of thenature of the key depression and independently of whether large or smallcharacters are being printed.

A more specific object is to provide a typewriter wherein the platen isshiftable for printing of small and large characters and the type barsare moved to printing position with automatically increasing force whenthe platen is in position for printing of" the large characters.

Other objects and advantages of the invention will appear from thespecification and drawings. An embodiment of the invention is shown inthe drawings, wherein- I Figure 1 is a right side elevation of thetypewriter with certain portions cut away to show the power drive;

Fig. 2 is a fragmental section and elevation taken from the left side ofthe machine;

Fig. 3 is a partial sectional elevation of the keys that control theplaten shift;

Fig. 4 is a partial rear elevation of the motor governor;

Fig. 5 is a detailed perspective of the driving drum for the platenshift; and

Fig. 6 is a, section through the drum of Fig. 5. The typewriter isprovided with a frame l5 (Fig. 1) supporting a raceway IS on which ismounted a traveling paper carriage C supporting a platen R The carriageis moved across the machine in the usual manner under the control of anescapement mechanism including a ratchet wheel I l, the details of theescapement mechanism not havingbeen illustrated or described as suchmechanisms are well known in the art.

about the platen 1?.

Power drive Themachine is preferably driven by an electric motor(Fig. 1) -on the armature shaft 2| of which is a worm 22 meshing with aworm wheel 23. The worm wheel 23 drives a shaft 24 through a releasingclutch 25, the shaft 24 having a bevel gear 26 on its end meshing withanother bevel gear 21 on the main drive shaft 28 of the machine.When-the typewriter is beingoperated, the motor drives the main driveshaft 28 continuously through the connections above described.

The releasing clutch is provided in order to prevent damage to themachine in the event it should become jammed in any way, such anexpedient being desirable because of the relatively light constructionof many of the typewriter parts. The'construction of this clutch, whichis more particularly described in my aforesaid original application, issuch as to enable the worm wheel 23 to drive the shaft 24 under allnormal conditions but, if a resistance should be encountered above apredetermined amount, the shaft 24 is released from the motor allowingthe motor to rotate without driving the machine.

The speed of the motor'is regulated by a gov- 2 ernor illustrated indetail in Fig. 4. Fixed to the armature'shaft 2| is a collar 30 carryinga pair of centrifugal members 3| bearing against the end of a plunger 32slidably, mounted in an extension of the collar 30. The plunger 32 bearsagainst an insulating plate 33 on the end of an angular switch arm 34pivoted at 35 on a lug 36 projecting upwardlyv from a stationary support31 bolted to but insulated from the motor housing by a bolt 38. Theswitch arm 34 carries a contact 39 urged by a spring 40 attached to theswitch arm into engagement with stationary contact 4| mounted on andinsulated from the support 31. The tension of spring 40 may be varied bymeans of an adjustable thumb nut 42 mounted in the.

support 31, one end of spring 40 being connected to an arm 43 carried bysaid nut.

As the speed of the motor increases, the centrifugal members 3| .flyoutward and push the plunger 32 to the right as viewed in Fig. 4. This.moves the switch arm 34 clockwise and tends to separate the contacts 39and 4| thereby opening the motor circuit and shutting off the supply ofcurrent to the motor. The motor speed then decreases until thecentrifugal members 3| move back to normal to allow the switch contactsto close. This action takes place very rapidly, the

contacts vibrating back'and forth to maintain just thev proper amount of-,current to enable the speed of the motor to remain substantiallyconstant. Different constant speeds can be had by adjusting the tensionof spring 40. While this 'form of governor is preferred, it is to beunderstood that any othersuitable type could be used.

- Type bar mechanism The type bars (not shown) are moved to printinPosition by the power drive under the control of key-levers 56 actuatedby keys 5| located in the keyboard at the forward part of the machine(Figs. 1 and 3). In order that the type bars may be driven to printingposition, they must be momentarily connected to the power drive and anovel construction for accomplishing this purpose is'fully shown anddescribed in my. said original application.

Briefly, a series of ratchet wheels 60 are mounted on the continuouslyrotating drive shaft 28, there being a ratchet wheel for each type bar.Each type bar is driven to printing position by being momentarilyconnected to its ratchet wheel 60, and this connection is effected bydepression of the key 5| for actuating the particular type bar. Eachtype bar can be connected to its ratchet wheel 60 by a pawl 6| pivotallysupported by a lever 62 that rocks about the axis of the shaft 28 and isconnected to the type bar in such a way that rocking movement of thelever 62 in clockwise direction moves the type bar toward printingposition.

The pawl 6| is urged clockwise toward a position for engaging theratchet wheel 60 by a spring 63 (Fi 2), but this pawl is normallyprevented from engaging the ratchet wheel by a detent 64 having a lip 65that projects in front of the nose of the pawl. The arrangement is suchthat when the key lever 50 is rocked clockwise by depression of a key5|, the detent 64, through suitable connections more particularlydescribed in my said original application is rocked clockwise to removeits lip 65 from in front of the nose of the pawl 6|. When thisoccurs,'the spring 63 snaps the pawl 6| into engagement with therotating ratchet wheel (Fig. 2) therebymoving the lever 62 clockwiseand, in turn, moves the type bar toward printing position. Thismovement, which is quite sudden, continues until the type bar is movedinto close proximity to the platen whereupon the driving connection isdisabled. The type bar and associated parts have enough momentum by thattime to cause the bar to continue its movement until it reaches theprinting position.

Disconnection-of the driving connections from the type bar isaccomplished through an irregularly shaped reversing or disconnectingmember 66 that is pivoted on the end of lever 62 and to the forward endof which the spring 63 controlling the pawl 6| isconnected. The member66 has a tail piece 61 operating in a slot in a comb plate 68 (Fig. 2),and'when the lever 62 is rocked clockwise to drive the type bar toprinting position, and as the type barreaches its position wherein it isto be released from the drive, the tail piece 61 of the member 66contacts the top of the comb plate slot so that the member 66 is rockedor flipped counterclockwise. This swings the spring 63 across the centerof the pivot of the pawl 6| so that the spring then tends to rock thepawl 6| clockwise out of engagement with the ratchet wheel 60. With,this arrangement, the pawl is positively, quickly and completelyknocked out of engagement with the ratchet wheelby a projecting portion69 of the member 66 which, I

during the rocking or flippingmovement of the member 66, strikes thelower face of the rear extension of the pawl 6| with a hammer-likeaction at about the time or shortly after the direction of action of thespring 63 is changed.

During the foregoing operation, the detent 64' is reset or released tothe position shown in Fig. 2 so that the pawl 6| again assumes theposition shown in that figure. v V

In the return of the type bar to its non-print- 5 ing position, afterrelease of the driving mechanism, the lever 62 swings counterclockwisetoward its normal position of Fig. 2. As the lever 62 thus swings, themember 66 moves with it and its tail piece 61 engages the bottom of theslot 1 in comb plate 68 so that the member 66 is flipped clockwise toits normal position thereby swinging the spring 63 back across the pivotof pawl 6| so that the spring 63 again acts to rotate the pawl towardengagement with the ratchet wheel 5 60, such engagement being prevented,however, by the lip 65 with the detent 64 which, having been returned tonormal position, blocks the pawl and holds it in inactive position.

It will thus be seen that when the key 5| is 20 depressed, the type barcorresponding to the key is connected to a continuously rotating ratchetwheel, which drives the type bar toward printing position, the type barbeing automatically disconnected just prior to the time it reachesprint- 25 ing position. The connection for each-type bar is individualand the construction is such that the connection and disconnection canbe made very rapidly and efliciently and without requiring anything buta very light key depression because 3 the depression of the key operatesonly very light parts.

Escapement mechanism As previously mentioned, the paper carriage ismoved across the machine under the control of an escapement mechanismincluding a ratchet wheel M. This ratchet wheel is controlled byescapement dogs l6 (Fig; 1) that are operated by an escapement baii (notshown), the construction 40 being very similar to that employed on aRoyal typewriter. In order for the carriage to be letter spaced, thebail is interconnected by suitable connections (more specifically setforth in my said original application) with the type bar operatinglevers 62, so that when each such lever is rocked clockwise, ashereinabove described, to move its type bar to printing position, thebail will be moved to actuate the escapement dogs 'lll to permitmovement of the carriage by the usual spring drum. The carriage is thusletter spaced each time a type bar is moved from printing position. Thecarriage can also be letter spaced by means of the spacing bar 80. Thisspacing bar may be interconnected with the escapement bail in any 55'desired manner, but preferably as shown and described in my saidoriginal application.

Power operated platen shift ing to supply the force by depression of akey. 70

Referring to Fig. 2, the carriage C with the platen P is supported onside plates 90 pivoted at 9|. By rocking these plates counterclockwise,

the carriage can be moved upward from its Fig. 4

2 position,' the upward movement being limited by a projection 92 thatengages an adjustable stop screw 93 on the typewriter frame. The sideplates are normally urged counterclockwise by a spring 94 connected atone end to the machine frame and at its other end to a lever 95 pivotedat 96 to one of the side plates and having a lip 91 projecting into ahole 98 in the side plate. This spring is not strong enough to raise theplaten, but it counteracts some of the weight of the carriage and platenand assists in making the raising operation easier. It also affords ayielding connection that serves a purpose that will be later described.

The side plates 90- are rocked counterclockwise to raise the platen bymeans of a link I00 that is' pulled to-the right as viewed in Fig. 2 bymeans of a flexible cable IOI wound around a drum I02 on the main driveshaft 28 of the machine. This cable is normally loose on the drum, butit may be tightened by depression of a platen shift keyin the followingmanner.

The platen shift key I03 shown in Fig. 3 is carried by a lever I04pivoted on the shaft I05 and provided with a lateral lug I06 adapted toengage a projection I01 on a lever I08 pivoted on the shaft I09. Thislever I00 carries a pin I I0 operating in a slot I II in the end of thelink I00 so that the lever has a slight movement relative to said link.The lever I08 has an arm II2 mounted rigidly on it, the other end of theflexible cable IOI being connected to the arm II2. When the platen shiftkey is depressed, the lever I08 is rocked clockwise carrying the arm'II2 with it which tightens the cable IOI about the drum. The drumimmediately grips the cable and pulls the link I00 to the right. Thisrocks the side plates 90 counterclockwise and raises the platen to-itsupper position. When the key is released the cable is loosened and theplaten returns to its lower position under its own weight and the weightof the paper carriage. A pin and slot connection between arm I I 2 andlever I08 permits adjustment 'of slack in cable I 0I (Fig. 2). v

The pin and slot connection between the lever I00 and the link I00permits the lever to move relative to the link to tighten the cableabout the drum,-but in the event the drum does not operate to raise theplaten the platen may be raised by hand through continued depression ofthe platen shift key which causes the stud I I0 to contact the end ofthe slot III and move the link I00 to the right to raise the platen.

If it is desired to hold the platen in raised position during a numberof operations of the type keys, the platen shift key must be helddepressed in which case the drum must rotate relative to the flexiblecable. Such action is permitted and successful operation is obtained bychoosing the right materials, it having been found that by making thedrum out of a self-lubricating fibre and by making the cable out of rawhide the cable will operate to raise the platen and, at the same time,will permit enough slipping to occur to enable the drum to rotate whenthe platen shift key is held depressed.

Provision is made for locking the platen shift keyin depressed positionand for this purpose a supplementary key H3 is provided mounted on alever I I4 pivoted on shaft I09. This lever has an arm I I5 connected toa wire I I6 that controlscertain parts of the machine whose functions itis not necessary to describe in the present application.

Referring to Fig. 3, the key lever II4 carries a stud III adapted toengage the end of a latch II8 pivoted at II9 to the machine frame andurged clockwise by a spring I20. This latch has a notch I2'I adapted toengage over a stud I22 on the lever I04 of the platen shift key I03.

When the key H3 is depressed the stud II'I contacts the edge of latchII8 which in turn contacts the stud I22 and moves the platen shift 5 keylever I04 downwardly. This movement continues until the latter has beenmoved to its operated position whereupon the notch I2I in the latch II8slips over the stud I22 and locks the lever I04 in lowered position. Inorder to 10 release the lever I04, it is merely necessary to depress theplaten shift key I03 which moves the stud I 22 downwardly a slightdistance and thereby releases the latch IIO which is snapped to itsupper. or released position by the spring 15 I20. This extra movement ofthe platen shift key is permitted by theyielding action of the spring 94and arm (Fig. 2) to the side plates of the platen shift frame. Althoughthe platen cannot move up any farther, the sprlngj94 will-20 yield. sothat the key I03 can befdepiessedi This spring also absorbs the shocksof violent'- key depressions.

Automatic control to obtain uniform printing Q It will be apparent that,when the platen is in the position where the large characters areoperative, more force will be required to obtain a printing impressionthan when the small 30 characters are employed. It is highly desirableto have all the printing impressions uniform. The present machine isprovided with a construction for automatically increasing the force withwhich the type bars are moved to printing 35 position when the largecharacters are employed.

Connected to a portion of the platen frame that is raised as the platenis moved to its upper position is a link I30 (Fig. 2) that is, in turn,40 connected through a spring I3I (Fig. 4) to a rod I32 projectingthrough an extension I33 of the switch arm 34 of the speed regulator ofthe electric motor. The rod I32 has a head I34 which, when the rod israised contacts the ex- 45 tension I33 to move the switch arm. When theplaten is raised, the link I30 is raised with it which raises the rodI32 and rocks the switch arm 34 counterclockwise. This tends to increasethe resistance to the centrifugal action 0 of arms 3I and increase thespeed of the motor,- which, of course, increases the speed of the maindrive shaft of the machine. It will be evident that, when the type barsare connected to ratchet wheels that are being driven at a higher rateof 55 speed, the type bars will be thrown to printing position with moreforce than under conditions when the ratchet wheels are revolving moreslowly. In other words, when the platen is raised to its upper positionthe motor is speeded up slight- 60 ly to impart more driving force tothe type bars so that the printing impression of the large type will bethe same as that of the small type, the

' entire operation being automatic.

This automatic control of the speed of the 65 motor can be variedthrough its connection illustrated in Fig. 4. The link I30 has anoffset" portion I35 carrying an adjustable screw I30 that contacts 2.lug I31 (Fig. 4) on an arm I33 pivoted on the link I30. The arm is urgedinto en- 7 gagement with the screw by a spring I39. By adjusting thescrew I36, the distance of the head I34 below the extension I33 can bevaried so as tovary the effect of the raising of the link I30 a on theswitch lever.

I- claim:

1. A typewriter having a platen, a power driving means, mechanismadapted to be actuated by said power driving-means to raise said platen,said mechanism including a power operated drum, a flexible beltsurrounding said drum, and means for tightening said belt on said drumto cause said power driving means to raise the platen.

2. A typewriter having a platen, a power driving means, mechanismoperable by said power driving means to raise said platen, and manuallyoperable means for conditioning said mechanism to cause it to raise saidplaten, said manually operable means having connections forautomatically raising said platen manually in the event said poweroperated mechanism does not function.

3. In a typewriting machine having a shift key for bringing capitalletters into function and a power roller driven by a, variable speedelectric motor; means responsive to a depression of said shift key foraccelerating said motor and said power roller when a capital letter isto be struck.

4. A power operated typewriter provided with impression making meanshaving large and small type, power driving means, driving connections'operated by said power driving means for moving said impression meansto impression making position, said machine being normally conditionedto cause the impressions to be made by said small type, means forconditioning the machine to make impressions from said large type, andspeed controlling means acting automatically as said machine isconditioned to make impressions from said large type to increase thespeed of said power driving means, said speed controlling means alsoacting to decrease the speed of said power driving means when themachine is returned to small type printing condition.

5.. A. power operated typewriter having a platen,

a plurality of movable type bars having large and'small type, anelectric motor having connectionsfor driving said type bars to printingposition, said typewriter being normally conditioned to cause a printingimpression to be made by the small type of said type bar, case shiftingmeans for changing the relative position of said platen and type bars tocause printing impressions to be made by said large type as said typebars are moved to printing position, and means conditioned by said caseshifting means for automatically increasing the speed of said electricmotor when said typewriter is conditioned to print from said large type.

- 6. A power operated typewriter having a platen, a plurality of movabletype bars having large and small type, an electric motor havingconnections for driving said type bars to printing posimeans conditionedas an incident tion, a governor for governing the speed of said motor,said typewriter being normally conditioned to cause the printingimpressions to be U made by the small type of said type bars, caseshifting means for changing the relative position of said platen andtype bars to cause printing impressions to be made by the large type,and to a "change in relative position between said platen and type barsfor automatically changing the condition of said governor to vary thespeed of said motor.

7. A power operated typewriter having a platen, a plurality of movabletype bars having large and small type, an electric motor havingconnections for driving said type bars to printing position, saidtypewriter being normally conditioned to' cause the printing impressionsto be made by the small type of said type bars, case shifting means forchanging the position of said platen relative to said type bar to causeprintingimpressions to be made by the large type, and means conditionedautomatically by said platen as it isshifted .for varying the speed ofsaid motor.

8. A typewriter having a platen, a power driving means, mechanismoperated by said driving means to raise said platen, said mechanismincluding a power driven member connected to said driving means, meansfor operatively connecting said member to and disconnecting it from saidplaten. means for operating said connecting means to operatively connectit to and disconnect it from said member to raise and lower said platen,said connecting means being so constructed and so arranged that itslip-engages said member in the raised position of said platen.

9. In a typewriter, power driving means, a platen, type bars havingsmall and capital letter type, means connecting said driving means tosaid type bars, means adapted to be connected to said driving means forshifting said platen, a shift key depressible for effecting connectionof said latter means with said driving means to move said platen to aposition for the printing of capital letters, and means responsive todepression of said shift key for increasing the speed of said drivingmeans.

10. In a typewriter, power driving means, a platen, type bars havingsmall and capital type, means for drive-connecting said type bars tosaid driving means, means adapted to be connected to said driving meansfor effecting relative shift movement between said platen and type barsto relatively position the same for printing capital letters, adepressible shift key for eifecting said connection of said lattermeans, and means responslve to depression of said shift key forincreasing the speed of said driving means.

' WALTER J. PASINSKI.

